How to send an email to an author on a specific date using date field specified in a node?

Question

In my content I have one date field which is entered by the author, who fills that as future estimate date like tomorrow or after 1 month. Depending on that estimated date, on that day mail should trigger.

Example: my date field is "weaning date" which the author will fill at as after one month on that day should trigger a mail.

Answer 1

You might use the Rules Scheduler module (included with Rules) for this. The following tutorial explains a case similar to yours: http://www.webwash.net/tutorials/how-send-follow-emails-using-rules-scheduler-drupal-7

In short, you would need to:

• create a "send email" component that sends an email with a user as parameter
• create a rule triggered when a node of your content type is modified
• set the action for that rule to an "scheduled component evaluation" that uses the "send email" component you created.
• in the "scheduled evaluation date" of the action you need to press the "switch to data selection" button, and then to select the date field of your node from the dropdown menu.

Note that the scheduled component evaluation is triggered by cron. You need to make sure that cron is configured correctly in your site.

Hope that helps,

Answer 2

Use the Rules module together with Rules Scheduler (a sub-module of it) for sending such eMails, as explained in the steps below.

Step 1: Create a field to store the "weaning" date

Assume your weaning date field has a machine name (say) field_weaning_date, for which only 1 date is allowed.

Step 2: Create a Rules "Component"

Here is the Rules Component to be created, in Rules export format (just import it in your own environment via copy-paste):

{ "rules_send_email_notification" : {
    "LABEL" : "Send eMail notification",
    "PLUGIN" : "action set",
    "OWNER" : "rules",
    "REQUIRES" : [ "rules" ],
    "USES VARIABLES" : { "user_to_notify" : { "label" : "User to be notified", "type" : "user" } },
    "ACTION SET" : [
      { "mail" : {
          "to" : [ "user-to-notify:mail" ],
          "subject" : "Reminder you requested",
          "message" : "This is a reminder that you asked for ...",
          "from" : "[site:mail]",
          "language" : [ "" ]
        }
      }
    ]
  }
}

Obviously, the Subject and Content of the eMail may need review / tuning, while you might also want to use some other From eMail ID.

Step 3: Create a "Rule" using the Rules Component

Here is the Rule to be created, in Rules export format (just import it in your own environment via copy-paste):

{ "rules_send_email_on_a_scheduled_date" : {
    "LABEL" : "Send eMail on a scheduled date",
    "PLUGIN" : "reaction rule",
    "OWNER" : "rules",
    "REQUIRES" : [ "rules", "rules_scheduler" ],
    "ON" : { "node_presave" : [] },
    "IF" : [
      { "entity_has_field" : { "entity" : [ "node" ], "field" : "field_weaning_date" } }
    ],
    "DO" : [
      { "schedule_delete" : { "component" : "rules_send_email_notification", "task" : "[node:nid]" } },
      { "schedule" : {
          "component" : "rules_send_email_notification",
          "date" : [ "node:field-weaning-date" ],
          "identifier" : "[node:nid]",
          "param_user_to_notify" : [ "node:author" ]
        }
      }
    ]
  }
}

The above rule refers to the Rules Component from the previous step.

The schedule_delete that is part of this rule is to ensure that previously "scheduled" reminders will get removed when updating the data field (so that it only triggers 1 reminder, and with the most recently entered date).

Attention: as per your specs in your question, if anybody different from the "author" ever updates that weaning date, the effect of doing so will be that:

1. no eMail will be send on the previously requested "weaning date" (if that is not what you want, then remove the schedule_delete part in the rules action in Step 3).
2. the "author" will receive another eMail, on the updated weaning date (if that is not what you want, then add a rules condition in Step 3 to verify that the editor's userid matches the author's userid).